Thursday, April 12, 2007 1:34 PM
Purpose: To Identify an unknown Hydrocarbon
Procedure: Procedure listed in handout "Organic Chemistry Experiment -- Hydrocarbons" Hazards: Open flame and hydrocarbons are flammable. Equations: 1. .
Unknown #: 1B s-6 Hyd-3 (colorless liquid) Data/Observations: Test Bromine addition Alkane Mixture of hexane and dichloromethane was originally clear liquid. After adding 3 drops red color Br2/CH2Cl 2 the solution turned orange. Orange color held. Alkene Alkene used was pentene. Originally clear liquid. After addition, solution turned yellowish at first but then turned clear after a few minutes of sitting. Alkyne Alkyne used was toluene. Originally clear liquid. After addition, solution turned orange. Orange maintained longer than alkene but eventually turned clear. Unknown Originally clear liquid. After addition of unknown, turned orange but eventually faded to clear color after a few minutes of sitting.
CHEM V01BL Page 1
Original color of potassium permanganate was a purple. Adding hexane had no visible change.
Original color: purple. Original color: purple. After addition of pentene, After addition of toluene, the color changed to a no change. red/brown with bubbles at the top.
Original color: purple After addition of unknown there was no color change but there was a collection of bubbles at the top similar to the alkene. Added 5 more drops and color still did not change.
Hexane No gray smoke
Pentene had black smoke Toluene had black smoke Unknown had black smoke. and smell that reminds me and black ash of snake fireworks. There was black ash coming off of flame too. N/A no need to perform N/A no need to perform 136C
Boiling Point 72C Determinatio n
Conclusion: Our unknown originally was orange with addition of bromine, but after a few minutes of sitting it turned clear. This is expla ined because...